Frequently, it is desirable to increase the tension of a valve spring in an automotive engine by inserting a shim or spacer of certain thickness dimension between the spring and the block.
It is an object of the invention to provide a valve spacer unit which compensates for spring wear in the block and on the spring cap and also on the spring ends.
It is also an object to provide a device which can compensate for loss of spring tension due to torsional relaxation resulting from heat and use and due to a possible change of dimension resulting from the wear of the valve and the block and also to a valve grinding operation.
It is an object further to provide a spacer unit which is particularly adapted to insulate the spring to a degree from the heat of the valve block and also to prevent circumferential creeping which increases the wear.
It is an object of the invention to provide a valve spacer ring shim which has radial grooves and radial ribs alternately spaced to provide increased cooling of the spring assembly without sacrificing the axial support needed at the spring base.